Department of Endocrinology, Qinghai University Affiliated Hospital, Xining, 810006, China.
Department of Gastroenterology, Qinghai University Affiliated Hospital, Xining, 810006, China.
J Orthop Surg Res. 2022 Mar 18;17(1):168. doi: 10.1186/s13018-022-03053-0.
Mesenchymal stem cells (MSCs) have emerged as the attractive candidates for cell therapy for cartilage repair in clinical therapy of osteoarthritis (OA). MiR-539-3p was reported to differentially express during chondrogenic differentiation of adipose stem cells (ASCs) by miRNA microarrays. The aim of the study was to investigate the effects and underlying mechanisms of miR-539-3p on chondrogenic differentiation of ASCs.
Human ASCs (hASCs) were obtained from liposuction and transfected with miR-539-3p mimic or inhibitor. Then, the cells were cultured in chondrogenic differentiation medium including transforming growth factor-β1 (TGF-β1).
Our results found that miR-539-3p was gradually down-regulated during chondrogenic differentiation of hASCs. MiR-539-3p overexpression inhibited TGF-β1-induced chondrogenic differentiation of hASCs, as supported by reducing the gene and protein expression of chondrogenic differentiation markers type II collagen alpha 1 (COL2A1), aggrecan (ACAN), and type II collagen. In contrast, miR-539-3p inhibitor significantly promoted the chondrogenic differentiation of hASCs. Dual luciferase reporter assay demonstrated that Sox9 was a direct target gene of miR-539-3p. The expression of SRY-box transcription factor 9 (Sox9) was up-regulated progressively over time during chondrogenic differentiation of hASCs. Additionally, Sox9 overexpression notably reversed chondrogenic differentiation of hASCs inhibited by miR-539-3p mimic, as demonstrated by the decreased expression of COL2A1, ACAN, and type II collagen.
Altogether, miR-539-3p inhibited chondrogenic differentiation of hASCs by targeting Sox9. MiR-539-3p may have significant clinical applications for use as a targeted therapy of OA.
间充质干细胞（MSCs）已成为治疗骨关节炎（OA）的细胞治疗中软骨修复的有吸引力的候选者。据 miRNA 微阵列报道，miR-539-3p 在脂肪干细胞（ASCs）的软骨分化过程中差异表达。本研究旨在探讨 miR-539-3p 对 ASCs 软骨分化的影响及其潜在机制。
从吸脂术中获得人脂肪干细胞（hASCs），并转染 miR-539-3p 模拟物或抑制剂。然后，将细胞在包含转化生长因子-β1（TGF-β1）的软骨分化培养基中培养。
我们的结果发现，miR-539-3p 在 hASCs 的软骨分化过程中逐渐下调。miR-539-3p 过表达抑制 TGF-β1 诱导的 hASCs 软骨分化，这得到了降低软骨分化标志物 II 型胶原α 1（COL2A1）、聚集蛋白聚糖（ACAN）和 II 型胶原的基因和蛋白表达的支持。相比之下，miR-539-3p 抑制剂显著促进 hASCs 的软骨分化。双荧光素酶报告基因检测表明 Sox9 是 miR-539-3p 的直接靶基因。Sox9 在 hASCs 的软骨分化过程中随着时间的推移逐渐上调。此外，Sox9 过表达显著逆转了 miR-539-3p 模拟物抑制的 hASCs 软骨分化，表现为 COL2A1、ACAN 和 II 型胶原表达降低。
总之，miR-539-3p 通过靶向 Sox9 抑制 hASCs 的软骨分化。miR-539-3p 可能具有作为 OA 靶向治疗的重要临床应用价值。
